[C320-list] "Canvas" Waterproofing Suggestions

[Dave Hupe]

Since purchasing our boat, I have used 303 Fabric Guard to attempt to restore water repellency on my aging Sunbrella canvas (bimini, mainsail cover, etc).   The first time I used it I really soaked the fabric.  While the fabric looked./felt nice afterward, rain did not continue to bead up and roll off as I anticipated. However, water did not seem to drip/pour through the fabric.  In subsequent applications, I applied the Fabric Guard as a heavy mist which seemed to provide about the same results (while using less of the material). 
The 303 Fabric Guard currently costs about $80/gallon on Amazon, which is pricey especially if applied heavily. I see Star Brite Waterproofing for about $45/gallon.  Star Brite also sells a water-based waterproofing for about $48/gallon. 
In preparation for the upcoming season, I am asking for your experiences/suggestions about what waterproofing to use and how to apply.

Dave Hupe
1994 C320 (#32) "Mayan Sun"
Holland, MI